Maybe try using the older "Namebench" app that still seems to work to establish the best recommended and fastest DNS server options, but it can take a bit if fiddling and renaming to get things working optimally and may need to be started and tried later with a new "scan".
voted for open dns
as it is easier to manage several different IP locations at once and I feel I can sleep better at night knowing google isn't knowing what I am preventing and what my IPs are..
OPENdns is very easy to use and has great GUI for their portal.
only advantage google has it is easy to remember .
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